I had not realized I needed Rmenu setup in order for Pseudo Saturn Kai ODE menu to work. Once I got Rmenu working, Pseudo Saturn Kai's menu worked straight away.If Rmenu works fine, this may be a bug or something related to ODE being unsupported in Pseudo Saturn Kai.
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I suggest implementing a more graceful fail mode when Rmenu is not present. Like I stated in my first post, I was just seeing the UI lock up when the Pseudo Saturn booted. There was no error message displayed. The only way to recover was to delete the Pseudo Saturn save data.